Russia's richest man began in the early days of perestroika by setting up the cooperative which became Menatep Bank, a household name before the 1998 financial crisis.

He took control of Yukos, Russia's biggest oil company which controls huge oil fields in western Siberia, during the loans-for-shares deals in the mid-1990s, when the oligarchs took over state assets for pennies in the pound.

After Vladimir Putin's election in March 2000, he mounted a slick PR campaign and opened the company to scrutiny, turning the former pariah into the poster boy for good corporate governance. Its shares shot up more than 1000% in 18 months from 1999, making him even richer.

Mr Yeltsin created a new Siberian oil company, Sibneft, out of state assets at their instigation; this was later signed over to them during the loans-for-shares deals.
A $15bn merger deal between Sibneft and Yukos netted him $3bn in cash and he reportedly sold his half share in Russian Aluminium (RusAl), one of the three biggest metal companies in the world.

He bought Chelsea football club for £140m in July and now lives in Britain. The only Russian business he has kept is Planeta Management, a vast agricultural enterprise worth an estimated $1bn.

Mikhail Fridman

Age 38

Estimated wealth $4.3bn

The head of the Alfa Group and its flagship, Alfa Bank, which emerged from the financial crisis as one of Russia's top commercial banks.

He bought the Tyumen oil company in a 1996 auction - its $1bn price tag was hailed as the first fair price for a Russian oil company. In February Alfa sold half of Tyumen to BP in a $7bn merger.

Alfa Group's other interests include hotels, tea, a leading supermarket chain and real estate as well as the bank and other businesses.

Boris Berezovsky

Age 57

Estimated value $3bn

A doctor of mathematics, Boris Berezovsky took over the car dealership network of AvtoVAZ, the maker of Ladas. From there he moved into banking before he and Mr Abramovich won control of Sibneft.

Mr Berezovsky put allies into the top jobs at companies such as Aeroflot, then directed their cashflows through his many subsidiaries in offshore havens. He also took control of ORT, the state-owned broadcaster, and was associated with its main advertising agency, a business with a multimillion-dollar turnover. He is also believed to own several newspapers.

In 2000 Mr Putin turned on Mr Berezovsky, who fled arrest warrants and investigations into his business dealings. He is now a political exile in London.

Oleg Deripaska

Age 34

Estimated value $1.5bn

The most politically powerful of the oligarchs emerged from the bloody aluminium wars as head of RusAl.

He maintains a low profile but is a leading member of The Family - the group that surrounded Boris Yeltsin when he was president. He is married to the daughter of Mr Yeltsin's senior political adviser.

Mr Deripaska is now battling to win control over the all-important power stations which supply the cheap electricity that makes the industry so profitable.

He has also been associated with the NIKoil financial group, which also works closely with Mr Abramovich.

Vladimir Potanin

Age 42

Estimated value £1.8bn

The blueblood among the oligarchs used foreign contacts gained through a plum job in the Soviet foreign affairs ministry to set up Uneximbank, which became Russia's biggest pre-crisis bank by using the state organisation money in its coffers to speculate against hyper-inflation.

Credited with devising the loans-for-shares deals, Mr Potanin took control of Norilsk Nickel, which supplies a quarter of the world's nickel, as well as Sidanco, an oil company he lost to Fridman after the 1998 crisis.

His Interros Group now has holdings in media and banking, and has recently set up one of Russia's two biggest agricultural holdings, as well as rapidly expanding in metallurgy by snapping up gold mines both in Russia and abroad.

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